Bierer B E, Barbosa J, Herrmann S, Burakoff S J
Department of Medicine, Brigham and Women's Hospital, Boston, MA.
J Immunol. 1988 May 15;140(10):3358-63.
Recently, it has been demonstrated that lymphocyte function-associated Ag (LFA-3) is a natural ligand for CD2 and that this receptor-ligand interaction functions in cell-cell adhesion. In this report, we demonstrate that LFA-3 plays a role in T cell activation. L cells were transfected with human genomic DNA and sorted for expression of LFA-3. We demonstrate that LFA-3+ L cells, together with anti-CD3 mAb or with suboptimal doses of PHA, stimulate proliferation of human peripheral blood T cells. Furthermore, thymocyte proliferation was induced by LFA-3+ L cells and suboptimal doses of PHA. Proliferation was inhibited by mAb directed against either CD2 or LFA-3. Stimulation of thymocytes by the combination of PHA and LFA-3+ L cells resulted in the increased expression of the IL-2R, as well as of the surface Ag 4F2, transferrin receptor, and HLA-DR. These data support the conclusion that LFA-3 plays a role in CD2-dependent T cell activation. LFA-3 is widely distributed and is expressed on all APC and target cells. Thus, the ability of the CD2/LFA-3 interaction to costimulate with an anti-CD3 mAb suggests that the CD2/LFA-3 interaction may be involved not only in an Ag-independent alternate pathway of T cell activation but also in Ag-specific T cell activation.
最近，已证实淋巴细胞功能相关抗原（LFA-3）是CD2的天然配体，且这种受体-配体相互作用在细胞间黏附中发挥作用。在本报告中，我们证明LFA-3在T细胞活化中起作用。用人基因组DNA转染L细胞，并对表达LFA-3的细胞进行分选。我们证明，LFA-3阳性L细胞与抗CD3单克隆抗体或次优剂量的PHA一起，可刺激人外周血T细胞增殖。此外，LFA-3阳性L细胞和次优剂量的PHA可诱导胸腺细胞增殖。针对CD2或LFA-3的单克隆抗体可抑制增殖。PHA与LFA-3阳性L细胞联合刺激胸腺细胞导致IL-2R以及表面抗原4F2、转铁蛋白受体和HLA-DR的表达增加。这些数据支持LFA-3在CD2依赖性T细胞活化中起作用的结论。LFA-3广泛分布，在所有抗原呈递细胞和靶细胞上均有表达。因此，CD2/LFA-3相互作用与抗CD3单克隆抗体共同刺激的能力表明，CD2/LFA-3相互作用可能不仅参与T细胞活化的非抗原依赖性替代途径，还参与抗原特异性T细胞活化。
